Fig. 1From: Light/dark cycle enhancement and energy consumption of tubular microalgal photobioreactors with discrete double inclined ribsa Smooth tubular PBR, named Type-0; b tubular PBR with a pair of ribs, named Type-1; c tubular PBR with two pairs of ribs, named Type-2; d tubular PBR with three pairs of ribs, named Type-3; e the detail of the ribs. Particles are released at z = 0.35 m of the tube center line where flow has been fully developed (Gómez-Pérez et al. 2015)Back to article page